Automatic fuel switch



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June 23, 1925.

M q. @@fw amA 55; yf f2# Z UNITED STATES PATENT OFFICE.

LEOPOLD F. BURGER, F RIVERSIDE, ILLINOIS, ASSIGNOR T0 INTERNATIONAL HAR- VESTER COMPANY, A CORPORATION OF NEW JERSEY.

` Patented June 2`3, 1925. i

AUTOMATI FUEL sWi'rcH Application tiled March 15, 1920. Serial No. 365,855.

To all whom 'it may concer/n.: ply of heavy fuel when a predetermined Be it known that I, LEOPOLD F. BURGER, a amount of heat has been absorbed. citizen of the United States, residing at A further object is to providel automatic Riverside, inthe county of Cook and State means dependeiit'on the temperature of a 6 of Illinois, have invented certain new and thermostatic member for shifting from a useful Improvements in Automatic Fuel light to a heavy fuel when the thermostatic Switches, of which the following is a full, member has attained -one temperature on a clear, and exact specification. i'isingvscale and for shifting from the heavy My invention relates to internal coinbusto the light fuel when the therinostatic mem- 10 vtion engines @adapted normally to operate ber hasvattained a considerably lower teinon a relatively heavy fuel, such as kerosene, f pei'ature on a descending scale. after 'having been started on a relatively A still further object 1s to provide means light fuel, such as gasoline or alcohol. In for quickly or instantaneously 'changing dev1ces of this character it has heretofore from fuel of one specific gravity to a fuel been customary to start the engine on the of another specific gravity when a prede' 70 light fuel and then shift to the heavier fuel te-rmined heat condition exists in the-engine i supply by manually controlled means when as contrasted with a gradual changing from in the opinion of the operator the tempei'- one fuel to the other.

ature of the engine cylinder is sufficiently The above and other objects will be ap- 20 high to vaporize the heavier oil. Another parent from the following description of the 75 means of operation has been to fill an auxilf embodiment of my invention illustrated in iary receptacle with a predetermined quanthe accompanying drawings in which tity of light fuel on which the engine will Figure 1 is a part sectional and part elestart, and when this is exhausted, the engine vational view showing the position of the will receive fuel from the main fuel reserparts when light fuel is being supplied to 80 voir containing the heavy fuel. Both of the engine; these methods have proved unsatisfactory in Figure 2 is a phantom view of the carpractice, since in the lirst case the operator buretor showing the position of the fuel has no definite means of knowing the tcmvalves when heavy fuel is being supplied perature conditions within the engine cylinto the engine;

der and may shift t0 the heavy oil too soon Figure 3 is a plan of the valve tripping thereby causing a waste of the heavy fuel mechanism. v or he may wait too long before shifting The number 5 indicates a carburetor havthereby using an unnecessarily large quaning a chamber 6 adapted to receive a supply tity of the expensive light fuel, or in the of kerosene and a chamber 7 adapted to be 90 second case the predetermined quantity of supplied with gasoline. The air inlet to the light fuel will be either larger or smaller carburetor is indicated at 8 and the outlet than necessary, dependent on the initial temfor the mixture leading to the intake maniperature conditions of the engine, the qual- Ifold or engine cylinder is indicated at 9. ity of mixture and other conditions of oper- A passage 10 controlled by a valve 11 and 95 ation. a regulated by the needle valve 12 leads from It is an object of my invention to provide the kerosene chamber tothe Venturi pasmeans dependent on the temperature condisage in the carburetor, the fuel being distions within the engine to automatically charged past the needle valve 1n atomized shift from light to heavy fuel when a cercondition into the throat of the Venturi pas- 10 tain predetermined temperature is reached sage. Likewise gasoline is supplied Afrom or exceeded and to automatically return to the chamber 7 to the Venturi tube through a the light fuel when the temperature depassage 13 controlled by a valve 14 and creases to a certain predetermined point. regulated by the needle valve 15. The

p 59 vAnother object of my invention is to provalves 11 and 14 have elongated stems which '105 vide thermostatica-lly controlled means deare pivotally or otherwise secured to oppopendent for its operation on heat absorbed site lends of the walkingbeam or rocker arm from the gases burned within the engine 16 which is pivoted to the carburetor bec linder to automatically cut 0E the supply tween the two valves. A valve tripping arm of light fuel to the engine and open the sup- 18 is also pivoted at one end at 17, the other 110 end being operatively connected to a push rod 19 for a purpose that presently ,will be apparent. lThe walking beam 16 and arm 18 are provided with T heads at one end as'shown in Fig. 3 and springs 20, 21 yield- -lngly `connect corresponding ends o'f these 'T-heads to quicklyv trip the walking beam I when shifting from one fuel to the other.

Ap-otion of the exhaust pipe is indicated at 22, the hot gases entering at 23 and passing to the muffler at 24. A thermostatic element 25 composed of an alloy having a relatively large coeflicient of expansion is secured at one end within the exhaust pipe, the other end being free to expand against a diaphragm 26 secured between a flange 27 on the exhaust pipe and a ange 28 on the return spring housing 29, slidably mounted within the housing is a piston or plunger 30 urged by the relatively stiff spring 31 against the short arm of a bell-crank lever 32 pivoted at 33 to a lixed part of the engine frame or cylinder. The long arm of the lever 32 is pivoted at 34 to one end ofthe push rod 19. r

Assuming that the engine has been started with the parts in the relative position shown in Fig. 1, gasoline will be fed to the carburetor through the passage 13 and valve 15. Hot exhaust gases from the engine passing through the exhaust pipe 22 will heat the thermostat 25 causing it to expand against the diaphragm 26 and lever 32. As the engine continues to run, the thermostat 7 will continue to absorb heat from the exhaust gases forcing the short arm of the lever 32 to the right against the tension of the spring 31 and raising the long arm of the lever and push rod 19. As the push rod moves slowly upward due to the continued expansion of the thermostat, it carries with i one end of the pivoted arm 18 and the t yip spring 2Q and 21. This movement con' tinues until the arm 18 reaches dead center position at which time the pull of the springs 20, 21 passes through the pivot point 17 of the lever 18 and Walking beam 16.

Up to this time there has been no movement of the valves 11 and 14 since the pull of the springs on the beam 16 has been exerted to hold down the end connectedto valve 11. However, as the lever 18 is raised beyond deadl center, the line of pull of the springs falls above the pivot point 17 and the beam or rocker 16 is instantaneously tripped or` rocked to the position shown in Fig; 2, closing the valve 14 and raising the valve 11 to supply kerosene to the carburetor.

The thermostat and its associated parts are so adjusted that when the expansion of the thermostat is suflicient to shift the valves, the engine cylinder will be heated to the proper temperature to operate eilicientl on the heavier fuel. Further expansion o the vthermostat after the valves have been shifted to supply heavy fuel ldoes not affect the valves but merely raisesthe lever 18 somewhat higher.

lVhen the engine is shut down, the thermostat 25 cools and contracts away from thc diaphragm 26. lAs this contraction takes place, the spring 31 forces the short arm of the bell crank to the left (Fig.I 1) thereby depressing the long arm and lowering the push rod 19 and arm 18. Lowering of the arm 18 does not affect the positions of the valves 11 and 14 until the armv again reaches dead center yposition on its downward movement, after which further movement Will carry the spring 20, 21 below the pivot point 17 and trip the valves from the position shown in Fig. 2 to that shown in/Fig. 1. The engine is then ready to be started again on gasoline whenever desired Without the operators having to shift any valves or adjust parts. Y

It will be seen from the above description that my invention automatically shifts from gasoline to kerosene supply when the temperature conditions Within the engine are such that the engine will operate eliiciently on the heavier fuel, and automatically shifts back to the light fuel when the engine is shut down or for lany reason cools below the minimum temperature at which the heavy fuel'can be effectively used.

It is also to be noted that there is a considerable range of temperature between the two points at which the valves 11 and 14 are tripped. Thus suppose that the rod 25 has expanded suiiciently to trip the valves to the position shown in Fig. 2 and then immediately begins. to cool and contract. The valves 11 and 14 will not be tripped back to the position shown in Fig. l until the contraction of the thermostat is suiicient to move the arm 18 in its downward course past dead center, and this may represent a considerable range of temperature. In practice, it is desirable to so ad just the parts that the shift from light to heavy fuel will not be' made until the temperature within the cylinder is somewhat above the minimum necessary for the proper use of the heavier fuel, in which case the shift from heavy to light fuel will not take place until the temperature is approximately at or somewhat below this minimum. However, I donot desire to be limited to any definite temperatures for changing from one fuel to another but wish it to be understood that the invention may be modied to effect the changes at any desired temperatures.

While 1 have described my invention as being adapted to use gasoline and kero sene, these terms are .but illustrative of relatively light and heavy fuels, the invention being adapted to the use of any two fuels of different specific gravities such as different grades of gasoline, alcohol and gasoline, kerosene and crude oil in engines of the Diesel type.

` I do not desireto be limited to the specific construction of my invention shown and described, since it will be apparent to those skilled in the art that the invention may be embodied in many modifications without departing from the spirit and scope of the invention defined by the appended claims. An obvious modification would be to omit the piston 30, spring 31, housing 29, and diaphragm 26, substituting therefor a' stuiing box through which the thermostat Would extend. The extended end of the thermostat would be provided with a slot to receive the short arm of the bellcrank to actuate the fuel switch in both directions. It will also be apparent to those skilled in the art that the thermostat 25 may receive its heat through means other than the exhaust gases. For example, the thermostat may be controlled by the temperature engine and work equally Well.

lVhat'I claim as my invention andI desire to secure byLetters Patent is:

l. In an automatic fuel switch for internal combustion engines, the combination of separate reservoirs for fuels of different of the cooling Water, or it mayextend into the combustion chamber of the specific gravities valve means controlling the passage of the fuels to the engine, an exhaust pipe for the engine, a thermostat secured at one end Within the exhaust pipe, the other end being free to move linearly by expansion, andV mechanism including a link and bell crank operatively connected to the valve means and adapted to be actuated by expansion of the thermostat for closing the paage for the lighter fuel and opening the passage for the heavier fuel.

2. In an automatic fuel switch for internal combustion engines, the combination of a carburetor having separate reservoirs for fuels of different specific gravities, a fuel passage leading from each reservoir to a common mixing chamber, valves controlling the respective passages, a rocker arm operatively connected at each end to one of the valves, a lever .pivoted at one end to the rocker arm between the connections to the valves, resilient means connected to one end of the rocker arm and to the free end of the lever and means dependent upon temperature conditions in the engine for actuating the lever to open one valve and close the other.

In testimony whereof I aiiix my signature.

LEOPOLD F. BURGER. 

